Developing efficient and low‐cost replacements for precious metals as electrocatalysts active in electrochemical reactions—the oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and oxygen reduction reaction (ORR)—is a top priority in renewable energy technology. In this work a highly active and very stable trifunctional electrocatalyst composed of Co2P embedded in Co, N, and P multi‐doped carbon has been synthesized using zeolitic imidazolate frameworks as precursors. The synergistic effects between Co2P and the multi‐heteroatom‐doped carbon substrates afford materials having electrocatalytic activities for HER, OER, and ORR, which are comparable—or even superior to—those of commercial RuO2 or Pt/C catalysts. Density functional theory calculations show that Co2P has a higher density of states at the Fermi level than ConP (0 < n < 2), which promotes electron transfer and intermediates adsorption in the catalytic process. Zinc–air batteries and water splitting devices assembled using the materials as electrode electrocatalysts show good performance and outstanding stability. This work represents a breakthrough in improving the catalytic performance of non‐precious metal electrocatalysts for OER, HER, and ORR, and opens new avenues for clean energy generation.
This review provides a timely and comprehensive overview of the recent progresses in the synthesis and application of phthalocyanine-based heterogeneous electrocatalysts, as well as the structure/composition–catalytic activity relationship, and future prospects.
Two‐dimensional conjugated aromatic networks (CAN) with ultra‐thin conjugated layers (ca. 3.5 nm) and high single‐metal‐atom‐site density (mass content of 10.7 wt %, and 0.73 metal atoms per nm2) are prepared via a facile pyrolysis‐free route involving a one‐step ball milling of the solid‐phase‐synthesized polyphthalocyanine. These materials display outstanding oxygen reduction reaction (ORR) mass activity of 47 mA mgcat.−1 represents 1.3‐ and 6.4‐fold enhancements compared to Pt and Pt/C in benchmark Pt/C, respectively. Moreover, the primary Zn‐air batteries constructed with CAN as an air electrode demonstrate a mass/volume power density of 880 W gcat.−1/615 W cmcat.−3 and stable long‐term operation for 100 h. This strategy offers a new way to design high‐performance electrocatalysts with atomic precision for use in other energy‐storage and conversion applications.
How to produce expressive molecular representations is a fundamental challenge in artificial intelligence-driven drug discovery. Graph neural network (GNN) has emerged as a powerful technique for modeling molecular data. However, previous supervised approaches usually suffer from the scarcity of labeled data and poor generalization capability. Here, we propose a novel molecular pre-training graph-based deep learning framework, named MPG, that learns molecular representations from large-scale unlabeled molecules. In MPG, we proposed a powerful GNN for modelling molecular graph named MolGNet, and designed an effective self-supervised strategy for pre-training the model at both the node and graph-level. After pre-training on 11 million unlabeled molecules, we revealed that MolGNet can capture valuable chemical insights to produce interpretable representation. The pre-trained MolGNet can be fine-tuned with just one additional output layer to create state-of-the-art models for a wide range of drug discovery tasks, including molecular properties prediction, drug-drug interaction and drug-target interaction, on 14 benchmark datasets. The pre-trained MolGNet in MPG has the potential to become an advanced molecular encoder in the drug discovery pipeline.
Two-dimensional
(2D) conjugated aromatic networks (CAN) have been
fabricated by ball milling of polymeric cobalt phthalocyanine precursors
edge-functionalized with different aromatic acid anhydride substituents.
The optimal CAN, obtained by using tetraphenylphthalic anhydride,
consists of uniform and thin (2.9 nm) layers with a high BET surface
(92 m2 g–1), resulting in well-defined
Co–N4 active sites with a high degree of exposure.
Thence, this material exhibits excellent electrocatalytic oxygen reduction
reaction (44 mA mgcat.
–1). Compared to
a benchmark Pt/C catalyst, this value denotes 1.2- and 6.0-fold enhancements,
respectively, in terms of the mass of Pt and total Pt/C. When utilized
as air electrode catalysts in Zn–air batteries, this material
provides a maximum areal power density (137 mW cm–2) and mass power density (0.68 W mgcat.
–1), values which also clearly surpass those of benchmark Pt/C catalyst.
This support-free and pyrolysis-free strategy developed in this work
delivers a novel route for the applications of 2D materials in clean
energy conversion and storage.
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